This is a resubmission for K02 MH01158, a Research Scientist Development Award application for Michael V. Vitiello, Ph.D. It will support Dr. Vitiello's research efforts which center on understanding the causes and consequences of age-related changes in sleep and circadian rhythms and provide him with the opportunity to expand his collaborative relationships and develop additional expertise relevant to his research interests. Dr. Vitiello proposes to examine the feasibility of possible interventions at three levels: first, to continue his study of the effects of fitness training. on the sleep quality and nighttime physiology of the elderly; second, to begin a new series of studies designed to evaluate the usefulness of anabolic hormones in improving sleep quality; and third, to develop a new collaborative relationship with the ultimate goal of examining the possibility of improving the sleep quality of the elderly with melatonin administration. Dr. Vitiello is currently conducting a study of the effects of fitness training on the sleep of the elderly. Preliminary analyses of the sleep and fitness project data set indicate that neither regular endurance nor stretching/flexibility training improves objective sleep quality in healthy elderly men and women. However, improvements in subjective sleep quality, circadian core body temperature rhythm and secretory patterns of growth hormone and plasma norepinephrine were observed. Analyses of this data set and those of the ancillary studies developed in conjunction with this study will continue. Dr. Vitiello also plans to examine the relationship between anabolic status and sleep quality in two studies. The first, a correlational study, will examine the relationships between anabolic status and sleep quality in a sample of healthy elderly men. The second, a prospective intervention, will examine the sleep quality of healthy elderly men and women before and after three months of treatment with growth hormone releasing factor or placebo. Dr. Vitiello will also develop a collaboration with Dr. Robert Sack and develop expertise in the circadian melatonin rhythm with the ultimate goal of examining this endocrine system as another possible intervention for age-related sleep disturbance.